NEMA enclosures are widely used in industrial and other applications to house hazardous parts. There are many types of NEMA enclosures, for indoor and/or outdoor use, which are categorized by numeric designation in accordance with their construction. For example, some NEMA enclosures are rated to provide mere access to hazardous parts, while others provide protection against ingress of solid foreign objects (falling dirt, circulating dust, lint, fibers etc.); ingress of water (hose down, splashing, occasional temporary submersion, occasional prolonged submersion); oil and coolant seepage, spraying and splashing; ingress of corrosive agents, and, other conditions. In order for an enclosure to receive a NEMA rating, strict construction standards promulgated by NEMA must be met.
Standards of construction for NEMA enclosures may also be employed in boxes or other containers for the storage of equipment, tools and the like in which protection against the types of conditions described above is desired. Boxes of this type, and NEMA enclosures generally, typically comprise a top panel, a bottom panel, a back panel and opposed side panels which are interconnected to form an interior. A front panel is hinged to the bottom panel and movable between open and closed positions. A seal is created between the front panel and the edges of each of the top, bottom and side panels of the enclosure which engage the front panel when closed in order to provide protection against the ingress of materials, such as discussed above, into the box interior.
Typically, NEMA enclosures and boxes which employ NEMA construction standards include a latch assembly for maintaining the front panel in a closed, locked position. Such latch assemblies generally comprise a latch coupled to opposed latch arms each movable between a retracted and extended position. In order to unlock the enclosure or box and permit opening of the front panel, a key must be inserted into the latch and turned so that the latch arms retract. The front panel is maintained in a closed, locked position by first closing the front panel, inserting the key into the latch and then turning it so that the latch arms are moved to the extended position. This presents a problem for a user who would like to close a box after having removed a tool or other equipment from it, but has his/her hands full and cannot easily close the front panel, and manipulate a key into the latch.